Sentinel lymph node biopsy a low-risk option in determining melanoma treatment

Key takeaways:

• Sentinel lymph node biopsy (SLNB) is a low-risk procedure that can reduce the need for complete lymph node dissection.
• Tumor characteristics can be evaluated to determine if SLNB is warranted.

CHICAGO — The use of sentinel lymph node biopsy can reduce the recurrence of nodules and the need for complete lymph node dissection in patients with melanoma, according to a speaker here.

Sentinel lymph node biopsy (SLNB) is completed by injecting radioactive tracer into the melanoma and using imaging to determine the exact melanoma location.

“Sentinel lymph node biopsy is a very important prognostic tool. It tells us often who needs adjuvant therapy, but also who needs close surveillance, who we should be following with CT scans or who we can turn loose and follow as needed,” Richard S. Hoehn, MD, assistant professor of surgery in the division of surgical oncology at University Hospitals Cleveland, said at the American Society for Dermatologic Surgery Annual Meeting.

Risks related to SLNB are minimal, with 11.3% of patients experiencing complications. These complications include wound infections, seromas and, rarely, lymphedema.

If SLNB comes back positive, the choice is then whether to do a complete lymph node dissection or to observe patients.

One study found that patients with positive sentinel nodes who received complete dissection and those who had serial observation with clinical exams and ultrasounds every 4 to 6 months showed no difference in melanoma-specific survival, according to Hoehn.

“Almost 90% of patients who had an immediate complete node dissection had no melanoma in those lymph nodes. And the patients who had immediate lymph node dissection had a four-times higher complication rate with regard to lymphedema. It’s a big surgery,” he said.

The takeaway, according to Hoehn, is that observation may be superior to emergency dissection.

Deciding which patients should receive SLNB can be determined by following published guidelines; however, Hoehn suggests any patients with melanoma that measures larger than 0.8 mm or is ulcerated should be considered, as well as patients whose tumors have different characteristics such as lymphovascular invasion, ulceration, mitosis and tumor subtype.

“If we look at specific tumor characteristics ... combining these characteristics can predict up to a 50% risk of a positive sentinel node,” Hoehn said. “So, tumor thickness alone or ulceration alone is not sufficient. If there are other high-risk characteristics, we should at least consider it.”